Effect of Network Topology on the Protein Adsorption Behavior of Hydrophilic Polymeric Coatings

Abstract

We prepared polyurethane (PU) network coatings with various cross-linking densities that were based on polypropylene glycol (PPG) and polytetramethylene glycol (PTMG) macrodiols with different lengths and containing similar amounts of hydrophilic methoxy polyethylene glycol (mPEG) dangling chains. Then, we investigated the effect of the network cross-linking density on the coating–water interface and protein adsorption through coarse-grained (CG) molecular dynamics (MD) simulations and experimental studies on molecular and macroscopic scales. Our CG MD simulations reveal that although a higher cross-linking density provides more connecting sites for hydrophilic dangling chains in the PU network, it diminishes the orientation of the hydrophilic dangling chains toward the water interface. Besides, our experimental results confirm that tighter networks with a similar total mPEG content display lower hydrophilicity (larger advancing water contact angle), a lower amount of mPEG migration to the interface (lower surface roughness measured by atomic force microscope), and higher human serum albumin and human fibrinogen adsorption, in agreement with CG MD simulation results.

PolySMart: a general coarse-grained molecular dynamics polymerization scheme

“…Crosslinked polymer networks are an important class of materials with a wide range of applications. [54][55][56] However, experimental characterization of the network structure to elucidate the relationship between the network topology and polymer properties is very challenging due to the insolubility of the polymer networks. Most of the earlier attempts to identify the properties of crosslinked polymer networks are based on statistical theories and models.…”

Surface Membrane Coating as a Versatile Platform for Modifying Antitumor Nanoparticles

“…105,106 Furthermore, antibiofouling characteristic resists the adsorption of nonspecific protein in blood. 107,108 However, the single coating of these synthesized polymers still has no targeting, and further specific ligand modification is needed. Therefore, in future antitumor applications, these synthetic polymer coatings are more suitable to employ their active carboxyl, amino, and hydroxyl groups as intermediates for connecting specifically targeted ligands.…”

“…Some other synthetic hydrophilic anionic polymers (such as Poly­(2-oxazoline) (POXs), poly­[ n -(2-hydroxypropyl) methylacrylamide] (PHPMA)) have been identified as suitable PEG substitutes, because of their better biological characteristics in vivo. These synthetic hydrophilic polymer coating can shield nanoparticles from aggregation and premature release and give NPs a “stealth effect”, reducing the recognition and removal of RES and promoting longer circulation. , Furthermore, antibiofouling characteristic resists the adsorption of nonspecific protein in blood. , However, the single coating of these synthesized polymers still has no targeting, and further specific ligand modification is needed. Therefore, in future antitumor applications, these synthetic polymer coatings are more suitable to employ their active carboxyl, amino, and hydroxyl groups as intermediates for connecting specifically targeted ligands.…”

Molecular Insight into the Effect of Polymer Topology on Wettability of Block Copolymers: The Case of Amphiphilic Polyurethanes

“…Another key parameter has been recently found to have a significant impact on time-dependent wettability and interfacial properties: the polymer topology. − For instance, Divandari et al introduced the effect of polymer topology on the interfacial properties of poly­(2-ethyl-2-oxazoline) (PEOXA) brushes on TiO 2 substrates, i.e., protein adsorption. They demonstrated how switching the grafted chains’ topology from linear to cyclic allowed precise control of the interfacial and physicochemical characteristics of polymer surfaces without the need for intolerable fabrications or complicated chemistries .…”